Method and apparatus for measuring substrate temperatures

Claim 1

A method of correcting temperature probe readings in a thermal processing chamber for heating a substrate, said method comprising: forming a reflecting cavity on one side of the substrate; heating the substrate to a process temperature; using a first probe, a second probe and at least a third probe to sample energy from said reflecting cavity, said first and third probes having associated therewith a first effective reflectivity and said second probe having associated therewith a second effective reflectivity, the sampled energy from the first probe producing a first temperature indication, the sampled energy from the second probe producing a second temperature indication and the sampled energy from the third probe producing a third temperature indication, and wherein the first and second effective reflectivities are different; from the first and second temperature indications, deriving a corrected temperature reading for the first probe where the corrected temperature reading is the sum of the first temperature indication and an adjustment temperature, said adjustment temperature derived from a difference between said first and second temperature indications, wherein the corrected temperature reading for the first probe is a more accurate indicator of an actual temperature of the substrate in the environment of the first probe than are uncorrected readings produced by the first and second probes; and from the adjustment temperature and the third temperature indication, deriving a corrected temperature reading for the third probe, wherein the corrected temperature reading for the third probe is a more accurate indicator of an actual temperature of the substrate in the environment of the third probe than are uncorrected readings produced by the third probe.

Claim 2

A method of correcting temperature probe readings in a thermal processing chamber for heating a substrate, said method comprising: forming a reflecting cavity on one side of the substrate; heating the substrate to a process temperature; using a first probe, a second probe and at least a third probe to sample energy from said reflecting cavity, said first and third probes having associated therewith a first effective reflectivity and said second probe having associated therewith a second effective reflectivity, the sampled energy from the first probe producing a first temperature indication, the sampled energy from the second probe producing a second temperature indication and the sampled energy from the third probe producing a third temperature indication, and wherein the first and second effective reflectivities are different; from the first and second temperature indications, deriving a corrected temperature reading for the first probe where the corrected temperature reading is the sum of the first temperature indication and an adjustment temperature, said adjustment temperature derived from a difference between said first and second temperature indications, wherein the corrected temperature reading for the first probe is a more accurate indicator of an actual temperature of the substrate in the environment of the first probe than are uncorrected readings produced by the first and second probes; and from the adjustment temperature and the third temperature indication, deriving a corrected temperature reading for the third probe, wherein the corrected temperature reading for the third probe is a more accurate indicator of an actual temperature of the substrate in the environment of the third probe than are uncorrected readings produced by the third probe.

Claim 12

An apparatus for measuring the temperature of a substrate in a thermal processing heating chamber, the apparatus comprising: a reflecting plate placed next to one surface of the substrate to form a reflecting cavity therebetween; a first probe positioned to receive energy from the reflecting cavity and produce a first temperature indication; a second probe positioned to receive energy from the reflecting cavity and produce a second temperature indication, said first probe having associated therewith a different effective reflectivity for said cavity than said second probe; at least one third probe positioned to receive energy from the reflecting cavity and produce a third temperature indication, said third probe having associated therewith approximately the same effective reflectivity for said cavity as said first probe; and a temperature measurement module which during processing receives the first, second and third temperature indications from said first, second and third probes, respectively, said module programmed to derive a corrected temperature reading for said first probe from said first and said second temperature indications, said corrected temperature reading for said first probe being the sum of said first temperature indication and a calculated adjustment temperature, said adjustment temperature calculated from a difference between said first and second temperature indications, said corrected temperature reading being a more accurate indicator of the actual temperature of the substrate at the region associated with the first probe than are uncorrected readings of said first and second probes, said temperature measurement module programmed to derive a corrected temperature reading for the third probe from the adjustment temperature and the third temperature indication, wherein the corrected temperature reading for the third probe is a more accurate indicator of an actual temperature of the substrate in the environment of the third probe than are uncorrected readings produced by the third probe.

Claim 13

An apparatus for measuring the temperature of a substrate in a thermal processing heating chamber, the apparatus comprising: a reflecting plate placed next to one surface of the substrate to form a reflecting cavity therebetween; a first probe positioned to receive energy from the reflecting cavity and produce a first temperature indication; a second probe positioned to receive energy from the reflecting cavity and produce a second temperature indication, said first probe having associated therewith a different effective reflectivity for said cavity than said second probe; at least one third probe positioned to receive energy from the reflecting cavity and produce a third temperature indication, said third probe having associated therewith approximately the same effective reflectivity for said cavity as said first probe; and a temperature measurement module which during processing receives the first, second and third temperature indications from said first, second and third probes, respectively, said module programmed to derive a corrected temperature reading for said first probe from said first and said second temperature indications, said corrected temperature reading for said first probe being the sum of said first temperature indication and a calculated adjustment temperature, said adjustment temperature calculated from a difference between said first and second temperature indications, said corrected temperature reading being a more accurate indicator of the actual temperature of the substrate at the region associated with the first probe than are uncorrected readings of said first and second probes, said temperature measurement module programmed to derive a corrected temperature reading for the third probe from the adjustment temperature and the third temperature indication, wherein the corrected temperature reading for the third probe is a more accurate indicator of an actual temperature of the substrate in the environment of the third probe than are uncorrected readings produced by the third probe.